diff -r adf0212d1dcc -r 4f43e64603ef cubicweb/cwgettext.py
--- a/cubicweb/cwgettext.py	Wed Nov 16 14:38:11 2016 +0100
+++ b/cubicweb/cwgettext.py	Thu Nov 17 10:47:52 2016 +0100
@@ -18,6 +18,8 @@
 
 import gettext
 
+from six import PY3
+
 
 class cwGNUTranslations(gettext.GNUTranslations):
     # The encoding of a msgctxt and a msgid in a .mo file is
@@ -83,6 +85,9 @@
             else:
                 return msgid2
 
+    if PY3:
+        ugettext = gettext.GNUTranslations.gettext
+
     def upgettext(self, context, message):
         ctxt_message_id = self.CONTEXT_ENCODING % (context, message)
         missing = object()